Spaced Out?

By By BroadCasting & Cable Staff

The FCC last week released its “white space” report on its tests of prototype unlicensed mobile devices, like laptops, that would use the spaces between digital TV channels for wireless broadband or home networking. One application, for example, would be to retransmit HD movies to numerous TVs in a household, which is currently beyond the capabilities of WiFi service using other spectrum.

That sounds great, except that recent FCC tests showed (and the FCC conceded they showed) the white space devices interfered with TV signals when they tried to use adjacent channels.

The report said that in those cases, the ability of the devices to sense other channels, and thus avoid interfering with them, was “severely impacted,” so much so that the engineers couldn't even measure how much. “This could impact significantly the ability of the devices to reliably detect TV signals within stations' service areas,” according to the report.

There was much the same interference problem for wireless microphones, used for TV sports productions and everything from Broadway shows to the Grand Ole Opry to church services. The FCC report found that, again, when the devices were too near a DTV channel, “the detection threshold was degraded such that it affected the ability of the devices to reliably detect the microphone signals.”

Moving to Main Street, there's also a problem with direct interference of cable reception in homes. “These tests showed that under certain circumstances, when the transmit antenna was placed in close proximity to a cable-connected TV, direct pick-up interference was observed,” the study said.

Let's recap. The tests showed problems with sensing TV stations, microphones and interference with cable TV reception. Some big bugs to fix, it seems to us.

So what did FCC engineers and Chairman Kevin Martin decide to do? The FCC declared: “Put the pedal to the metal.”

The report's rabbit-hole logic is the tests weren't meant to determine whether the devices worked, but whether under certain conditions the devices could work—what they called “proof of concept.” All it proves is the FCC appears willing to jeopardize the new digital TV regime to get a gold star for “uses spectrum efficiently.”

If there is even a possibility that the price of that efficiency is to decimate the DTV band through foreseeable consequences of interference to TV reception, the price is too high.

Martin appears willing to risk it. And even more troubling, a senior FCC source says there are probably at least two other votes—that would be a majority—for the item, though they were described as not carved in stone. If the recent past is prologue, just because the chairman has scheduled a vote for Nov. 4 doesn't mean the item will stay on the agenda.

We certainly hope it doesn't. With a new administration about to take over, with the DTV transition in full swing, and with no clear path to a white spaces regime without grave interference, this is no time to race ahead into an uncertain future with the equally uncertain future of broadcasters' business model riding on the outcome.